When designing your custom frame program, there are options you have for preserving the special item within the frame. Premium Clear: 2.5mm regular clear glass. Conservation Clear: Glass that blocks up to 99% of UV light to help protect items from fading and discoloration. Conservation Non-Glare: Our best museum grade glass locks up to 99% of UV light to help protect from fading and discoloration & no glare. Plexiglass: If glass is not an option, plexiglass is available. Excellent for shipping and self assembly/kit items.